switch ($_REQUEST['step']) { // user  
case 1: //step 1
echo "Hi, what's your name?"; //
break;
case 2:
echo "Hi " . $_REQUEST['value1'] . ", where do you live?"; //  $_REQUEST['value1'] 
break;
case 3:
echo "Well, welcome to this hello world bot, " . $_REQUEST['value1'] . "
from " . $_REQUEST['value2'] . ".";
break;
}

?>
